The invention relates to a cassette provided with magnetic tape and comprising a housing having two parallel main walls interconnected by transverse walls, of which one transverse wall constitutes a cassette front wall having two pressure-roller openings and one magnetic-head opening; a sliding cover which comprises a front portion situated near the front wall and extending parallel thereto, main portions adjoining the front portion and overlying the main walls of the housing, and a pressure-roller aperture and a magnetic-head aperture, which sliding cover is movable between a closed position and an open position and covers the openings in the housing in the closed position and exposes the openings in the open position, which cassette has a thickness in a direction perpendicular to the main walls.
A cassette of the type defined in the opening paragraph is described in the non-prepublished Dutch Patent Application filed under number 9000348 (=attorneys Docket No. PHN 13,235) herein incorporated by reference. Said Application describes a system comprising said cassette and an apparatus for recording and/or reproducing digital audio signals on/from the magnetic tape in the cassette. This system aims at replacing the well-known Compact Cassette system according to which signals are read and written in analog form on the magnetic tape in conformity with the internal standard IEC 94-7. The proposed cassettes and apparatuses of the digital system are largely identical, at least mechanically, to those of the Compact Cassette system to enable the apparatuses of the digital system to play-back the analog Compact Cassettes.
The cassette of the digital system is a modification of the Compact Cassette. The most important modifications concern the omission of the thickened part which is present at the open side of the Compact Cassette and the presence of a sliding cover to close the open side. The tape transport in the apparatuses is effected by means of a capstan and a pressure roller which presses the magnetic tape against the capstan. As the mechanical part of an apparatus of the digital system is substantially the same as that of the Compact Cassette system the housing of the digital cassette should have substantially the same dimensions, apart from the thickened part of the Compact Cassette, and should have a similar space for cooperation with a pressure roller as the Compact Cassette System. As the dimension of the pressure-roller opening in the well-known Compact Cassette in a direction perpendicular to the main walls is larger than the thickness of remaining part of the housing (8.6 millimeter) and therefore also of the described digital cassette, and one of the main walls of both cassettes cooperates with a similar surface in the apparatus, the pressure-roller openings in the housing of said digital cassette and the pressure-roller aperture in the sliding cover should extend into both main walls of the housing and into both main portions of the sliding cover, respectively. Pressure-roller openings in the housing and the pressure-roller aperture in the sliding cover extending into the main walls and main portions weaken the housing and the sliding cover, respectively. This increases the likelihood of deformation of the housing and of the sliding cover during use, and hence the likelihood of the sliding cover being canted relative to the housing, which may render the cassette unserviceable.